I share your lifestyle of having to be cautious. I know it gets a little challenging sometimes. But the trade-off is that I’m still alive and having a great 2nd life. Though my life has changed I don’t feel too limited in my normal activities. Not sure if it helps you to know you’re not alone in this. There are millions of us who are immunocompromised and have to be careful, especially since Covid came on the scene.
As long as you mask up, remember to have personal space between people, wash hands often, elbow bump instead of hand shakes, hand sanitizer, etc., you should be able to have a fairly normal life.

You mentioned that the Rituxan has depleted your B-Cells. There’s so much more to your immune system than that. There’s an entire other half that is unaffected by this treatment.
B cells make antibodies and are only one part of your immune system. The other part being your T-cells.
The Rituximab did what it set out to do, with suppressing the B-Cell production to slow the progression of your leukemia.
The Rituximab only reduces the B cell production but should not eliminate them, which is a step in the right direction. After B-cells get told what to do by the immune system, they produce neutralizing antibodies for the specific invader. The neutralizing antibodies block the ability of an invader to attack the cells by bonding to the active sites, making them the first responders of the immune system.

But you have a whole second piece to your immune system that’s in effect, but unaffected by the Drug. T-cells enter the picture later and provide a variety of functions that includes destroying the infected cells. These are the guys that pick up after the antibodies have done their roll, making it your second line of defense.

You have always had a fully functioning second line of defense and the Rituximab should have cleared your system by now. So the B-Cell population should be regenerating.

Let me know if this is helpful?